PHILADELPHIA (973espn.com) - As currently constructed the Tennessee Titans aren't your typical NFL team, and that can result in its own set of challenges.

The Titans want to run the football for a number of reasons and the fuel for that starts with necessity in that Tennessee simply doesn't have the weapons to throw the football consistently even before Marcus Mariota's elbow injury affected the quarterback's grip or tight end Delanie Walker, perhaps Tennessee's best offensive player, went down with a dislocated ankle in the team's season-opener against Miami.

The Titans were built to run the football with former coach Mike Mularkey inventing a system he called exotic smash-mouth and current mentor Mike Vrabel is following suit, at least until he and his offensive coordinator Matt LaFleur, a former Sean McVay acolyte, get the kind of players in Nashville who can run a more "modern" offense.

Mariota, the widely athletic former University of Oregon star, is the centerpiece of things now and figures to remain so whenever the playmakers demarcation line is crossed.

One of the more unique QBs in the NFL, the biggest headache Mariota can give a defense right now, however, especially with the nerve issue in his throwing elbow bogging him down, is with his legs.

"Well, it puts everybody, defensively, a little bit more on a sense of urgency with some of the zone-read and they do a lot of things – a multiple offense, whether it's the zone-read, wildcat situations with runners back there, and just even the play-action pass that can come off of it," Eagles coach Doug Pederson said when discussing the Titans' offense.

The tools are there to run the football, a big back in Derrick Henry, a shifty change-of-pace guy in Dion Lewis and two top-tier tackles fueling the offensive line -- Taylor Lewan and Jack Conklin. The lynchpin and what makes it so difficult to defend at times is the impact of dealing with the extra body you usually don't have to account for, the QB Mariota.

"Zone-read possibility. Could they run a pistol, a speed-option," defensive end Chris Long said. "It's all in your head before the snap and hopefully it doesn't slow you down."

The Eagles, though, are more qualified than most because their defense sees so many run-pass options in practice.

"It's a unique style," Pederson admitted. "Our defense is very comfortable having obviously practiced and played against our offense."

The zone-read part of it complicates things even further and the theme this week, as it always is when you are playing against a running QB, is alignment and assignment.

"It's a discipline," Pederson said. "It's all about discipline, where your eyes are, training your eyes during the week, studying the film, and making sure your reads and your keys are right on point."

973espn.com Prediction: Eagles 17, Titans 13

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen